FIG. 1 is a flow chart depicting a conventional method 10 for fabricating a conventional perpendicular magnetic recording (PMR) transducer. For simplicity, some steps are omitted. The conventional method 10 is used for providing a PMR pole in an aluminum oxide layer. A trench is formed in the aluminum oxide layer, via step 12. The top of the trench is wider than the trench bottom. As a result, the PMR pole formed therein will have its top surface wider than its bottom. Consequently, the sidewalls of the PMR pole will have a reverse angle. A Ru gap layer is deposited, via step 14. The Ru gap layer is used in forming a side gap. Step 14 typically includes depositing the Ru gap layer using chemical vapor deposition (CVD). The conventional PMR pole materials are plated, via step 16. Step 16 may include plating ferromagnetic pole materials as well as seed and/or other layer(s). A chemical mechanical planarization (CMP) is then performed, via step 18. The write gap and top shield are then deposited, via steps 20 and 22, respectively.
FIG. 2 depicts plan and air-bearing surface (ABS) views of a portion of a conventional PMR transducer 50 formed using the conventional method 10. The conventional transducer 50 includes an underlayer 52, Ru gap layer 54 which is deposited in the trench (not shown). The pole 60, write gap 70 and top shield 80 are also shown. Thus, using the conventional method 10, the pole 60 may be formed.
Although the conventional method 10 may provide the conventional PMR transducer 50, there may be drawbacks. The performance of the conventional PMR transducer 50 is desired to be improved. The magnetic track width variation is also desired to be reduced. In order to do so, the geometry of the conventional pole 60 is desired to be well controlled during fabrication. For example, the radius of curvature at the corner 66 near the nose length is desired to be small. Using the method 10, the radius of curvature at the corner 64 of the Ru gap layer 54 is small. However, inside the Ru gap layer 54, the corner 66 of the pole 60 is less sharp. Stated differently, the radius of curvature of the pole 60 is larger. Consequently, the magnetic track width variation may be larger than desired. In addition, as can be seen in FIG. 2, the variation in the width of the side gap layers 54 may be larger than desired. Performance and manufacturability of the conventional magnetic recording transducer 50 may thus be adversely affected. Accordingly, what is needed is an improved method for fabricating a PMR transducer.